diff options
Diffstat (limited to 'synapse/events/spamcheck.py')
| -rw-r--r-- | synapse/events/spamcheck.py | 306 |
1 files changed, 218 insertions, 88 deletions
diff --git a/synapse/events/spamcheck.py b/synapse/events/spamcheck.py index d5fa195094..45ec96dfc1 100644 --- a/synapse/events/spamcheck.py +++ b/synapse/events/spamcheck.py @@ -15,7 +15,18 @@ import inspect import logging -from typing import TYPE_CHECKING, Any, Collection, Dict, List, Optional, Tuple, Union +from typing import ( + TYPE_CHECKING, + Any, + Awaitable, + Callable, + Collection, + Dict, + List, + Optional, + Tuple, + Union, +) from synapse.rest.media.v1._base import FileInfo from synapse.rest.media.v1.media_storage import ReadableFileWrapper @@ -29,20 +40,186 @@ if TYPE_CHECKING: logger = logging.getLogger(__name__) +CHECK_EVENT_FOR_SPAM_CALLBACK = Callable[ + ["synapse.events.EventBase"], + Awaitable[Union[bool, str]], +] +USER_MAY_INVITE_CALLBACK = Callable[[str, str, str], Awaitable[bool]] +USER_MAY_CREATE_ROOM_CALLBACK = Callable[[str], Awaitable[bool]] +USER_MAY_CREATE_ROOM_ALIAS_CALLBACK = Callable[[str, RoomAlias], Awaitable[bool]] +USER_MAY_PUBLISH_ROOM_CALLBACK = Callable[[str, str], Awaitable[bool]] +CHECK_USERNAME_FOR_SPAM_CALLBACK = Callable[[Dict[str, str]], Awaitable[bool]] +LEGACY_CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[ + [ + Optional[dict], + Optional[str], + Collection[Tuple[str, str]], + ], + Awaitable[RegistrationBehaviour], +] +CHECK_REGISTRATION_FOR_SPAM_CALLBACK = Callable[ + [ + Optional[dict], + Optional[str], + Collection[Tuple[str, str]], + Optional[str], + ], + Awaitable[RegistrationBehaviour], +] +CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK = Callable[ + [ReadableFileWrapper, FileInfo], + Awaitable[bool], +] + + +def load_legacy_spam_checkers(hs: "synapse.server.HomeServer"): + """Wrapper that loads spam checkers configured using the old configuration, and + registers the spam checker hooks they implement. + """ + spam_checkers = [] # type: List[Any] + api = hs.get_module_api() + for module, config in hs.config.spam_checkers: + # Older spam checkers don't accept the `api` argument, so we + # try and detect support. + spam_args = inspect.getfullargspec(module) + if "api" in spam_args.args: + spam_checkers.append(module(config=config, api=api)) + else: + spam_checkers.append(module(config=config)) + + # The known spam checker hooks. If a spam checker module implements a method + # which name appears in this set, we'll want to register it. + spam_checker_methods = { + "check_event_for_spam", + "user_may_invite", + "user_may_create_room", + "user_may_create_room_alias", + "user_may_publish_room", + "check_username_for_spam", + "check_registration_for_spam", + "check_media_file_for_spam", + } + + for spam_checker in spam_checkers: + # Methods on legacy spam checkers might not be async, so we wrap them around a + # wrapper that will call maybe_awaitable on the result. + def async_wrapper(f: Optional[Callable]) -> Optional[Callable[..., Awaitable]]: + # f might be None if the callback isn't implemented by the module. In this + # case we don't want to register a callback at all so we return None. + if f is None: + return None + + if f.__name__ == "check_registration_for_spam": + checker_args = inspect.signature(f) + if len(checker_args.parameters) == 3: + # Backwards compatibility; some modules might implement a hook that + # doesn't expect a 4th argument. In this case, wrap it in a function + # that gives it only 3 arguments and drops the auth_provider_id on + # the floor. + def wrapper( + email_threepid: Optional[dict], + username: Optional[str], + request_info: Collection[Tuple[str, str]], + auth_provider_id: Optional[str], + ) -> Union[Awaitable[RegistrationBehaviour], RegistrationBehaviour]: + # We've already made sure f is not None above, but mypy doesn't + # do well across function boundaries so we need to tell it f is + # definitely not None. + assert f is not None + + return f( + email_threepid, + username, + request_info, + ) + + f = wrapper + elif len(checker_args.parameters) != 4: + raise RuntimeError( + "Bad signature for callback check_registration_for_spam", + ) + + def run(*args, **kwargs): + # We've already made sure f is not None above, but mypy doesn't do well + # across function boundaries so we need to tell it f is definitely not + # None. + assert f is not None + + return maybe_awaitable(f(*args, **kwargs)) + + return run + + # Register the hooks through the module API. + hooks = { + hook: async_wrapper(getattr(spam_checker, hook, None)) + for hook in spam_checker_methods + } + + api.register_spam_checker_callbacks(**hooks) + class SpamChecker: - def __init__(self, hs: "synapse.server.HomeServer"): - self.spam_checkers = [] # type: List[Any] - api = hs.get_module_api() - - for module, config in hs.config.spam_checkers: - # Older spam checkers don't accept the `api` argument, so we - # try and detect support. - spam_args = inspect.getfullargspec(module) - if "api" in spam_args.args: - self.spam_checkers.append(module(config=config, api=api)) - else: - self.spam_checkers.append(module(config=config)) + def __init__(self): + self._check_event_for_spam_callbacks: List[CHECK_EVENT_FOR_SPAM_CALLBACK] = [] + self._user_may_invite_callbacks: List[USER_MAY_INVITE_CALLBACK] = [] + self._user_may_create_room_callbacks: List[USER_MAY_CREATE_ROOM_CALLBACK] = [] + self._user_may_create_room_alias_callbacks: List[ + USER_MAY_CREATE_ROOM_ALIAS_CALLBACK + ] = [] + self._user_may_publish_room_callbacks: List[USER_MAY_PUBLISH_ROOM_CALLBACK] = [] + self._check_username_for_spam_callbacks: List[ + CHECK_USERNAME_FOR_SPAM_CALLBACK + ] = [] + self._check_registration_for_spam_callbacks: List[ + CHECK_REGISTRATION_FOR_SPAM_CALLBACK + ] = [] + self._check_media_file_for_spam_callbacks: List[ + CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK + ] = [] + + def register_callbacks( + self, + check_event_for_spam: Optional[CHECK_EVENT_FOR_SPAM_CALLBACK] = None, + user_may_invite: Optional[USER_MAY_INVITE_CALLBACK] = None, + user_may_create_room: Optional[USER_MAY_CREATE_ROOM_CALLBACK] = None, + user_may_create_room_alias: Optional[ + USER_MAY_CREATE_ROOM_ALIAS_CALLBACK + ] = None, + user_may_publish_room: Optional[USER_MAY_PUBLISH_ROOM_CALLBACK] = None, + check_username_for_spam: Optional[CHECK_USERNAME_FOR_SPAM_CALLBACK] = None, + check_registration_for_spam: Optional[ + CHECK_REGISTRATION_FOR_SPAM_CALLBACK + ] = None, + check_media_file_for_spam: Optional[CHECK_MEDIA_FILE_FOR_SPAM_CALLBACK] = None, + ): + """Register callbacks from module for each hook.""" + if check_event_for_spam is not None: + self._check_event_for_spam_callbacks.append(check_event_for_spam) + + if user_may_invite is not None: + self._user_may_invite_callbacks.append(user_may_invite) + + if user_may_create_room is not None: + self._user_may_create_room_callbacks.append(user_may_create_room) + + if user_may_create_room_alias is not None: + self._user_may_create_room_alias_callbacks.append( + user_may_create_room_alias, + ) + + if user_may_publish_room is not None: + self._user_may_publish_room_callbacks.append(user_may_publish_room) + + if check_username_for_spam is not None: + self._check_username_for_spam_callbacks.append(check_username_for_spam) + + if check_registration_for_spam is not None: + self._check_registration_for_spam_callbacks.append( + check_registration_for_spam, + ) + + if check_media_file_for_spam is not None: + self._check_media_file_for_spam_callbacks.append(check_media_file_for_spam) async def check_event_for_spam( self, event: "synapse.events.EventBase" @@ -60,9 +237,10 @@ class SpamChecker: True or a string if the event is spammy. If a string is returned it will be used as the error message returned to the user. """ - for spam_checker in self.spam_checkers: - if await maybe_awaitable(spam_checker.check_event_for_spam(event)): - return True + for callback in self._check_event_for_spam_callbacks: + res = await callback(event) # type: Union[bool, str] + if res: + return res return False @@ -81,15 +259,8 @@ class SpamChecker: Returns: True if the user may send an invite, otherwise False """ - for spam_checker in self.spam_checkers: - if ( - await maybe_awaitable( - spam_checker.user_may_invite( - inviter_userid, invitee_userid, room_id - ) - ) - is False - ): + for callback in self._user_may_invite_callbacks: + if await callback(inviter_userid, invitee_userid, room_id) is False: return False return True @@ -105,11 +276,8 @@ class SpamChecker: Returns: True if the user may create a room, otherwise False """ - for spam_checker in self.spam_checkers: - if ( - await maybe_awaitable(spam_checker.user_may_create_room(userid)) - is False - ): + for callback in self._user_may_create_room_callbacks: + if await callback(userid) is False: return False return True @@ -128,13 +296,8 @@ class SpamChecker: Returns: True if the user may create a room alias, otherwise False """ - for spam_checker in self.spam_checkers: - if ( - await maybe_awaitable( - spam_checker.user_may_create_room_alias(userid, room_alias) - ) - is False - ): + for callback in self._user_may_create_room_alias_callbacks: + if await callback(userid, room_alias) is False: return False return True @@ -151,13 +314,8 @@ class SpamChecker: Returns: True if the user may publish the room, otherwise False """ - for spam_checker in self.spam_checkers: - if ( - await maybe_awaitable( - spam_checker.user_may_publish_room(userid, room_id) - ) - is False - ): + for callback in self._user_may_publish_room_callbacks: + if await callback(userid, room_id) is False: return False return True @@ -177,15 +335,11 @@ class SpamChecker: Returns: True if the user is spammy. """ - for spam_checker in self.spam_checkers: - # For backwards compatibility, only run if the method exists on the - # spam checker - checker = getattr(spam_checker, "check_username_for_spam", None) - if checker: - # Make a copy of the user profile object to ensure the spam checker - # cannot modify it. - if await maybe_awaitable(checker(user_profile.copy())): - return True + for callback in self._check_username_for_spam_callbacks: + # Make a copy of the user profile object to ensure the spam checker cannot + # modify it. + if await callback(user_profile.copy()): + return True return False @@ -211,33 +365,13 @@ class SpamChecker: Enum for how the request should be handled """ - for spam_checker in self.spam_checkers: - # For backwards compatibility, only run if the method exists on the - # spam checker - checker = getattr(spam_checker, "check_registration_for_spam", None) - if checker: - # Provide auth_provider_id if the function supports it - checker_args = inspect.signature(checker) - if len(checker_args.parameters) == 4: - d = checker( - email_threepid, - username, - request_info, - auth_provider_id, - ) - elif len(checker_args.parameters) == 3: - d = checker(email_threepid, username, request_info) - else: - logger.error( - "Invalid signature for %s.check_registration_for_spam. Denying registration", - spam_checker.__module__, - ) - return RegistrationBehaviour.DENY - - behaviour = await maybe_awaitable(d) - assert isinstance(behaviour, RegistrationBehaviour) - if behaviour != RegistrationBehaviour.ALLOW: - return behaviour + for callback in self._check_registration_for_spam_callbacks: + behaviour = await ( + callback(email_threepid, username, request_info, auth_provider_id) + ) + assert isinstance(behaviour, RegistrationBehaviour) + if behaviour != RegistrationBehaviour.ALLOW: + return behaviour return RegistrationBehaviour.ALLOW @@ -275,13 +409,9 @@ class SpamChecker: allowed. """ - for spam_checker in self.spam_checkers: - # For backwards compatibility, only run if the method exists on the - # spam checker - checker = getattr(spam_checker, "check_media_file_for_spam", None) - if checker: - spam = await maybe_awaitable(checker(file_wrapper, file_info)) - if spam: - return True + for callback in self._check_media_file_for_spam_callbacks: + spam = await callback(file_wrapper, file_info) + if spam: + return True return False |